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Sam Fowlkes
ACA Safety and Rescue Committee Chair
347 Paddlers Trail
347 Paddlers Trail
Sylva, NC  28779
T. 828 586-6563
F. 828 586-9649
336-202-5531
whitewatersam@gmail.com
www.whitewater-rescue.com
 
Rescue PFD Study Update!
DISCUSSION OF TECHNICAL ASPECTS OF RESCUE PFDs


At the conclusion of the Rescue PFD field evaluations completed earlier this year we indicated we would discuss more specific information about the current styles and function of rescue vests.

Rescue vests have evolved as hybrids of type III personal flotation devices (PFD) and are designed to provide buoyancy and freedom of movement when paddling whitewater, yet can be employed as a rescue tool.  The primary difference between a regular vest and a rescue vest is the inclusion of a Quick Release Harness Belt System (QRHS).  A rescuer can attach to a rescue line and be belayed by a second rescuer for a rescue application, however, the entire QRHS must release under tension to allow the rescuer to become free of the rescue line but still wearing the PFD.

The USCG approval process is conducted and audited by Underwriter Laboratories.  Most testing is done at a laboratory in calm water.  Because of intended use a rescue vest may be subjected to in river rescue applications, we see a need for the approval testing to be conducted in a whitewater river environment.

Factors in PFD Construction

o Buoyancy—minimum flotation required by the USCG is 15.5 lbs.  Most of the current popular rescue vests worn principally by kayakers and canoeists have flotation that ranges from about 16 lbs to less than 18 lbs buoyancy.  The Lotus P-Vest (16 lbs, 7oz) offers an optional implant that fits into the center pocket, giving 2 lbs 8oz additional flotation.  Refer to heading on Trends and Styles in Vest Design.

In the PFD review we found that some of the vests had only marginal buoyancy when river swimming in turbulent water.  Swift moving water is quite different than calmer, slower water.  Because of the turbulent hydraulic effects of whitewater, a swimmer will be underwater for periods of time regardless of the amount of flotation.
o Buoyant material that doesn’t absorb water.  PE and PVC have been common foams used in vests.  PE is more rigid, less expensive and has been the most environmentally friendly option in foam choices, whereas PVC is softer, with excellent recovery properties but more expensive.  Another type being used is acrylonitrile butadiene rubber (NBR) which is soft and also environmentally friendly.
o Fabric and thread strong enough to withstand the rigors of whitewater use.
o Adjustment straps and hardware items that resist degradation from water/sun.
o Pockets that drain, are durable and do not protrude excessively when full.
o Shoulder adjustments that insure a snug fit and will not slip under tension. 
o Correct fit—not only should a vest be comfortable for paddling, it should not ride up the torso after being adjusted.  This is especially important when aggressively swimming because vests that ride up can impede progress and block the vision of the rescuer in the water.
o Impact protection—a vest should have sufficient torso and side impact protection from falling or bumping into objects during water rescues.
o Webbing sewn into the shoulders straps and vest body is integral to the vest. 

Trends and Styles in PFD Design

Whitewater kayakers, open canoeists, sit-on-top paddlers, inflatable kayaks, etc, prefer a vest that allows freedom of movement, and kayak paddlers favor one that does not interfere with the spray skirt.  For big water rivers many rafters may prefer a higher profile, longer style that has considerably more buoyancy.

o Low Profile—these styles have large armholes and have the buoyant material positioned lower on the torso.  Examples: Astral 300 R, Lotus P-Vest, and Extrasport Pro Creeker.
o Short Waist, High Cut Models—in these models the buoyant material is positioned higher up on the torso but they too have large armholes for freedom of movement.  Some of the choices are Stohlquist X-Tract, MTI Pro Play and Patriot, Lotus Rio Pro and Kokotat ProFit.
o Higher Profile (or longer style)—these styles have increased buoyancy and come in either full length models or short waist versions.  Frequently used by boaters in big water (rafters, professionals, or rescue personnel), they have 22 lbs or more of buoyancy.  Some examples are Extrasport Hi Float and Fury models, MTI Patriot, and models by Force 6 of Canada.
o Universal Fit—these styles accommodate a variety of ranges mostly from sizes 30-56 and are used in big water paddling, in rescue classes (fit a variety of participants), or by rescue personnel.  Examples: Sterns Versatile Rescue 1650 and Extrasport Universal Fit.

During the field reviews we raised several questions about differences we noted in the effectiveness of the flotation of vests.  We plan to conduct more field trials to determine a more suitable minimum flotation amount needed for self-rescuing in bigger water, or for performing a swimming rescue of another swimmer (either tethered or not).

Some reviewers reported they felt the short waist; high cut styles provided the most effective flotation when swimming aggressively.  Because a man’s center of gravity is higher up the body as contrasted to a lower center in women, we want to learn more definitive information about different style vests and the flotation they provide, for both men and women paddlers.

A few companies make regular vests that specifically fit the female profile but of the rescue vests we’ve reviewed, only the Astral Buoyancy Company makes one for women—called the WonderPro ($185).  We also want to learn if low profile styles provide more effective flotation for women than other styles when swimming aggressively or self-rescuing. 

We’ll report on what we learned at a later date.
How Vests are Sized

Rescue vests are usually sized in three different ways.  Regular sizes (S, M, L, XL, and XXL).  Overlapping usually are S/M, L/XL, etc. and Universal Fit (one size fits all) usually range from sizes 30—56.  It’s important that the strap adjustment system not permit the vest to creep up the torso when swimming, when the vest is under tension, or after releasing the QRHS and while still swimming.  Adjustment straps should prevent gaps/spaces at the waist and chest areas to prevent collecting water when river swimming. A properly fitting vest will also minimize heat loss when paddling in cold environments. 

The PFD field review indicated that regular sizes tended to fit more snugly without having gaps or spaces where water could collect.  Overlapping sizes accommodate a wider range of sizes but have disadvantages.  A smaller paddler wearing an overlapping size vest (such as 42-54) may not be able to adjust the straps well enough to prevent it riding up the torso.  In addition, the excess length of the straps after being adjusted may present a snagging risk.  Universal Fit vests, because of a wider range in sizes, may be even harder to fit with paddlers in the smaller sizing range.  When a larger size wearer adjusts the straps to the maximum size, side panel (rib area) torso protection is usually lacking.

SAFETY CONSIDERATIONS

A rescue vest is a multi-purpose rescue tool that has limitations and requires training and consistent practice.  Intricate knowledge of the workings of a rescue vest can make the difference between a successful rescue and a possible accident or injury.

o The Quick Release Harness System consists of several components: a tri-glide stainless steel buckle and a black cam buckle with a red toggle cord attached for releasing the harness belt system.  A steel ‘O’ ring in back allows rescuers to be connected to a rescue line.  For some models the harness belt is sewn in, on others it can be removed and the vest used as a type III PFD without the harness belt.
o An auxiliary self-tether (also called cows tail, pig tail, or swiftwater tow tether), allows rescuers to self-connect to a rescue line.  It must be safely stowed to prevent entanglement when not in use because tethers that hang excessively create a snagging potential.  One or two models have a side pouch for safely stowing the tether when not in use. 
o A harness belt passing through the tri-glide buckle may jam/stick because the rescuer did not pull the toggle straight out on release (perpendicular to belt), by too much excess belt length (causes friction), or because the belt end is not left flat when the excess is shortened and seared.
o Manufacturers recommend that 25 lbs of force is needed to make the harness system release reliably under a load.  With less force the belt releases more slowly or not at all.  Rescuers must be practiced in inserting the thumbs into the cam buckle/tri-glide assembly to make the belt release if there isn’t enough load on the line. 

*(refer to the section on QRHS and testing the release with commercial scales). 

o A locking carabiner must be used when attaching a rescue line to the ‘O’ ring or with the self-tether.  A non-locking carabiner might inadvertently clip into some other part of the rescue vest, thereby nullifying the ability of the rescuer to release from the rescue line.  In swiftwater rescue classes, pre-determined signals are established to pendulum a rescuer to shore in case of emergency. 
o A locking carabiner can be used in place of a lost ‘O’ ring, or else a rescue line can be tied directly into the ‘O’ ring with an appropriate secure knot.

One choice would be to pass the harness belt through just one of the slots in the tri-glide and then through the cam buckle to insure a light load would release properly. 

Always be certain to thread the QRHS as the manufacturer requires when executing tethered lowers or live bait techniques.

BODY AND TORSO PROTECTION

Many personal injuries that occur in both live rescues and rescue workshops are caused from tripping and falling along the riverbank.  For protection against impact, a vest should have sufficient cushioning in the upper and lower torso and in the side panels.  Some companies are now including side impact panels made to protect the rib area of the torso.  Not only does this give more cushioning, it adds needed flotation.

Upper torso cushioning is a main drawback of low profile style vests.  Most all current models also lack impact protection in the clavicle or shoulder area because of the necessity for freedom of movement when paddling.  One brand had wider padded shoulder straps that provided some protection to the clavicle/shoulder area.  More study is needed to determine ways to have this protection without compromising paddling freedom or swimming movements. 

DAY AND NIGHT VISIBILITY

Although manufacturers use a variety of colors for rescue vests, the brighter colors (red, yellow, orange and mango) provide better contrast in daytime functions.  Some lighter green and blue colors, as well as black, blend in too much with the color of river water and are not as visible.  Rescuers should be clearly visible to one another when working on rescue functions, especially in dim light. 

Most vests include reflective tape/piping on both the front and back panels for night visibility and a few provide excellent night visibility.  Some do lack any reflective tape over the tops of the shoulders. 

ATTACHMENT CAPABILITY AND STORAGE POCKETS

Maintaining a streamlined profile is important when carrying items in pockets or attaching things to the outside of the vest because protruding items present a significant snagging risk to a swimmer or rescuer working in the water.

o Pocket or storage space should be adequate for such rescue items as carabiners, prusik loops, webbing (rescue sling), fire starter, CPR pocket mask or other items.  Pockets must close securely, drain well, not collect water and should be easily accessible.  Some of the current low profile models have only a center pocket and when full it protrudes quite a bit.  This might impede swimming progress or self-rescuing over a strainer.
o Some models have carrying capacity in the back panel for a rope or other rescue items that leave the hands free for swimming.  Others allow the attachment of additional pockets to increase storage space or for adding water bladders.
o At the conclusion of the PFD review we suggested having attachment points for knife, whistle, etc. that have breakaway capability to lessen potential for snagging.

Quick Release Harness System (QRHS)

One important function of a rescue vest is for tethered rescuer lowers in strong river current, a technique that substantially increases risk to rescuers.  Because rescuers can withstand only so much pressure acting on the body, the force of the current (class of rapids) becomes a limiting factor in whether or not to employ a tethered rescue.

More than twenty years ago, Raymond Row and Graham Wardle of the British Canoe Union published a small booklet discussing the positioning of the harness belt and ‘O’ ring on the back.  It stated, “that the point of attachment [of the rescue line to the ‘O’ ring] be in exactly the correct spot, that is, about mid-point between the shoulder blades.”  This point of attachment was intended to float the rescue swimmer almost horizontally in a ‘planing’ posture when performing rescue lowers (with the feet close to the surface and the head remaining above water).  Actually, when performing tethered lowers, rescuers can lessen the force of the water pressure on the body by arching the back during the maneuver allowing the water flow to pass under the body.

Information about the ‘O’ ring attachment point is virtually unchanged in recent years.  Booklets published by some manufacturers have similar statements to the Row/Wardle booklet—“the attachment point for the rescue line is positioned to hold the rescuer’s head above water, and the harness should be across the chest.”  Slim Ray’s Swiftwater Rescue Handbook also explains—“the attachment point should be positioned to hold the head above water in swift current [normally…. between the shoulder blades”]. 

Older models some of us had experience with (these were made by Extrasport and Stohlquist) did locate the attachment point up close between the shoulder blades with the harness belt crossing mid sternum.  These were higher cut styles with smaller armholes that fit higher on the torso.  During the tethered rescuer trials of the recent field reviews, we noted significant differences in the attachment point and position of the harness belt on the various vests.  One short waist; high cut brand that was stressful to rescuers on lowers angled the harness belt upward from the front torso to the back attachment point.  This vest also lacked any side torso cushioning.  *We plan to conduct river trials and specifically compare different style vests relative to how the ‘O’ ring and harness belt are located, and which are the least stressful and most comfortable when doing lowering techniques. 

Testing with a set of commercial scales revealed a range in the amount of force necessary to make the harness system of different vests release under a load.  Results varied from 12 lbs to 48 lbs. The harness belt should release consistently and easily.  Friction in a harness system depends on several factors: the number of loops the belt feeds through, the position of the belt across the front torso, and excess length of the belt end.  Through practice a rescuer will learn exactly what to expect from the harness system on a rescue vest.  It is a good idea to frequently check the harness belt for fraying edges.

Summary

As with boat designs, trends and styles in rescue vests continue to evolve.  Whitewater boaters desire and need a vest that strikes a balance between sufficient buoyancy for self-rescuing in turbulent water, freedom of movement for paddling comfort, and performance capability for rescue functions.  As we have said in this report, we feel there are compelling reasons for rescue vests to have more flotation and added cushioning for torso and side protection.

Some short waist; higher cut models have 22—26.5 lbs of buoyancy that provides excellent flotation, but are somewhat cumbersome and bulky for whitewater kayaking (as reported in our field reviews).  Certain low profile designs are very comfortable, provide excellent freedom of paddling movement, have some good rescue design ideas, but we believe need more buoyancy for swimming in heavier, turbulent current.

As research and experience continue to provide answers to questions, hopefully manufacturers will be able to supply rescue vests with a suitable combination of buoyancy and rescue and safety features.  The perfect vest, like the perfect boat, may never be made, but they continue to improve.

We encourage boaters to participate in swiftwater rescue training and become familiar with the strengths and limitations of rescue vests.  They are a valuable rescue option but require consistent practice to be fully aware of their performance capabilities.


December, 2005, Jim Simmons.  Other Instructors who helped compile this report were Vernon Seaman, Jim Jones, Tom Burroughs, and Tim Jones.
                             
ADDITIONAL RESCUE PFD REVIEWS

Continuation of Table 1.  Results of Review of Lotus Rio Pro.   *(followed by a discussion of 2005 Astral 300 R)  Both  were completed in September, 2005.           

A)  Five point scale used for objective evaluations:
     5--Excellent; 4--Good Performance; 3--Acceptable; 2--Needs Improving; 1--Poor    

Review Criteria:                   Lotus Rio Pro    

Ease entry and removal                4+
Snug fit and comfortable               4
  shoulder adjustment                   4
  torso adjustment system            4
Visibility daytime in water             5
Visibility nighttime                        5
Carrying capacity basic items       3
  easy access to pockets             4-
Fits different size paddlers well     4-
Freedom mvt. when paddling        4
Buoyancy in swiftwater swims      4
Swimming ease wearing vest        4
Doesn't ride up when wet/in use    4
QRHS when under tension           4
  ease of releasing toggle             5
  snug fit after releasing toggle      4
Self-rescue capability swimming
   over strainer                             4
Upper torso protection                 4
Lower torso protection                 4-
  *(vest is longer in back)
Side panel protection (rib area)     3-

B) Specifications and Options Available for the Lotus Rio Pro: review vest was Aztec Yellow with 17lbs, 4oz flotation, USCG approved, 500 denier Cordura fabric, QRHS is semi-integral, comes with a self-tether (optional), has lash tabs/attachments, two front pockets (one rather small), reflective tape and sold in overlapping sizes.  Retail $180.

C) As done with the initial review in April (of seven vests), each reviewer completed a subjective evaluation that included: pros and cons; likes or dislikes; and what worked/didn't work well.  A composite of the subjective summaries for the Lotus Rio Pro is given below.


Discussion of LOTUS Rio Pro  (Comes in Aztec Yellow, Red), $180  *A Lotus representative informed us that some sizes are currently sold out)

This vest is a companion to the Lotus P-Vest and advertised as having features suitable for both paddlers and professional rescuers.  It is higher cut than the P-Vest and a front entry that is easy on and off.  Comes in overlapped sizes (the review vest was L/XL--size range 41-47).  It provided a good fit and very adequate buoyancy for larger rescuers and did not ride up when aggressively swimming.  Did not fit as comfortably for one smaller size person which often happens with overlapping sizes because of space between the vest and the upper torso area after adjustment.

Torso adjustments are easy to make and when cinched the vest is reasonably comfortable, however for smaller rescuers within the sizing range, excess strap length presents a snagging potential.  Because it is short waist, high cut style it has adequate upper torso protection and the wide, padded shoulder straps give some protection on the clavicle area.  The shoulder padding fabric felt a bit stiff but shoulders adjusted easily with the pro-glide buckles (buckles fit inside a stretch neoprene sleeve).  These pro-glide buckles are easy to adjust and release, but it's possible they could inadvertently loosen if bumped or when aggressively swimming.

As with most vests side panel torso protection needs to be better.  The Rio Pro provided good freedom of movement when paddling and aggressively swimming.

The Aztec Yellow color is easily seen in daylight and strips of reflective tape along the front zipper and down the backside give good low light or night visibility.  A right front stretch mesh pocket is conveniently placed and provides adequate storage capacity for rescue items.  A smaller second pocket can only accommodate small items like keys, or maybe one carabiner.  It comes with two lash tabs for attachments such as whistle or knife.

The QRH Belt system released easily (among the best of all vests reviewed) and we liked the stiffer seat belt type webbing because it does not wrinkle as other softer weaves are prone to do.  The vest feels comfortable when performing Lowers in river current and stayed in place after releasing the QRHS and while swimming.

Reviewers liked the ease of entry and buoyancy of this vest, and especially the release of the QRHS when doing rescuer Lowers in the current.  As described by the manufacturer this vest performs very adequately for rescue applications and we liked the fact the back panel is slightly longer for more low back protection.  Overall, the Rio Pro is a solid vest and got good marks.


Discussion of ASTRAL 300 R, 2005 Model (Comes in: Red/Black or Orange/Black), $185  *(we previously included the 2004 Astral in the earlier PFD review)

The low profile Astral for 2005 continues as a streamlined pullover.  It is easier to put on and take off that the previous model and adjusts easily and quickly.  It continues in overlapped sizing--the one reviewed was L/XL (42--54 inches in chest).  This is a  comfortable vest for both paddling freedom of movement and rescue work and stays in place well when aggressively swimming.  Mobility when swimming in this vest is also good.  The QRHS belt (1.5 inches instead of the standard 2 inch) distributes pressure on the torso evenly during rescue lowers and the release of harness belt worked easily.  

Reviewers liked the tubular spectra webbing self-tether that stuffs into a side pocket to reduce snagging potential when not in use.  It also has a front spectra "extrication loop" that an Astral representative explained was not to be used for belaying, but as a connection point for attempting to rescue an entrapped boater.

Front pocket storage capacity is good and it can accommodate what Astral calls their "quick throw" rope bag.  With the rope stowed here and the center pocket full it seemed to protrude more that we liked. The vest also has a back panel slot for storage.  Shoulders have strips of reflective piping for night vision but it could use more on the body of the vest.   Side inserts provides much needed side torso and rib area protection.

This vest is advertised for extreme conditions and has some distinct features for rescue applications requiring its owner to be familiar with its capabilities and performance.  We appreciate forward thinking of the manufacturer regarding new design ideas.  As we reported in our previous review, a main drawback for low profile designs is the lack of upper torso protection which is a tradeoff for the comfort/mobility performance.  In addition, a couple of larger paddlers reported the vest did not float them as well as they would have liked on the aggressive swims and rescue drills.

There is much to like about this vest, especially paddling comfort.    Astral also makes a rescue vest for female paddlers called the WonderPro ($185).

 
 
 
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